Question

我得到了一张包含4个字段的表格：

[record_id] is the pk
[pay_serial_number] should always be increased +1
[worker_id] each worker has unique id
[content] just some content.

我被告知添加功能有一个错误，并跳过许多序列号。我需要创建一个查询，为每个工人打印缺少的序列号。

[worker_id][missing serial number]
[worker_id][missing serial number]
[worker_id][missing serial number]

打印此类表格的最快捷有效的方法是什么。

Answer 1

查找“缺失”的序列号有点难。它们不在数据中，因此您必须生成它们。

然而，找到缺失的范围并不难。为此，使用相关子查询来获取下一个序列号（或使用lead()或lag()函数（如果可用）。然后找到任何有间隙的地方。

以下是查询：

select worker_id, pay_serial_number + 1 as FirstMissing,
       (nextpsn - pay_serial_number - 1) as NumMissing
from (select t.*,
             (select min(pay_serial_number)
              from t_workers_pay t2
              where t2.worker_id = t.worker_id and -- ASSUMING SEQUENTIAL FOR A WORKER
                    t2.pay_serial_number > t.pay_serial_number
             ) as nextpsn
      from t_workers_pay t
     ) t
where nextpsn - pay_serial_number > 1;

Inc sql查询验证

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